


Savage

by CasualCazz



Category: Undertale (Video Game)
Genre: Ahegao, Alternate Universe - Underfell, Birthing, Blowjobs, Breeding, Drugs, Kidnapping, Knotting, Lactation, M/M, Mind Break, Mpreg, Petplay, Pregnancy, Squirting, Stockholm Syndrome, Underfell Doggo - Freeform, Underfell Sans, collaring, kustard - Freeform, non-con
Language: English
Status: Completed
Published: 2018-06-13
Updated: 2018-06-25
Packaged: 2019-05-21 22:55:17
Rating: Explicit
Warnings: Rape/Non-Con
Chapters: 5
Words: 3,899
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/14924417
Author URL: https://archiveofourown.org/users/CasualCazz/pseuds/CasualCazz
Summary: Undertale Sans, named Classic, is kidnapped by Underfell Doggo and is turned into a sex slave.





	1. Chapter 1

**Author's Note:**

> A/N: OHHH MYYYY GODDD. IT’S DONE. IT’S FINALLY DONE. AFTER TWO MONTHS OF PAIN I’VE FINISHED THIS. WHOOO. 
> 
> Yes, this is a multichapter smut fic, where each chapter will be released everyday. Chapter two will come tomorrow :) Honestly, this fic tired me out so much but I had a lot of fun with this kinky goodness.

“JUST LEAVE AND NEVER COME BACK!” Red throws a vase against the wall, only missing Classic by a couple inches.

The Tale monster snarls, his eye flaring furiously with his magic. He clenches his fist, but doesn’t summon an attack. Instead, Classic throws him his middle fingers and slams the door behind him, shattering a window. Needing to clear his head and too angry to focus on teleporting, the softer monster stuffs his hands in his pocket and mindlessly wanders around in the snow, following the trail into the forest. He mumbles to himself as the ground crunches under him, too wrapped up in his own thoughts to notice the shadow following him.

“Well, well, what do we have ‘ere?” a gruff voice snarls behind him.

Classic’s body runs cold and he turns around, but before he could teleport away, a large black dog with attaches an anti-magic collar around his neck, pulling on the leash. The dog monster tugs on the chain harshly and Classic yelps, falling to his knees.

“I think I caught myself a shiny new toy,” the monster grins, barring his yellowed fangs and drags Classic deeper into the forest.

The small skeleton tries cry and scream, but he’s too far from town for anyone to hear him. Or for anyone to care for that matter. The monster pushes him inside a small cabin at the edge of the forest. Nothing too grandeur, just a single room building with a small bed, a brick fireplace, and refrigerator and a stove. Only one dimly lit flickering light bulb illuminates the cabin, the windows blackened so no outside light comes through. The fell monster wraps the chained leash around the bed and flops on it himself. Classic sits on the cold wooden floor, tugging at the collar or trying to break the chain itself. The dog monster seems unconcerned with the skeleton’s efforts and rolls to the side. 

Upon closer inspection, Classic concludes that this monster was this world’s version of Doggo, albeit with coarse midnight black fur and glaring red eyes. He’s much bigger than his Doggo as well, with ripped muscles, claws as sharp as a knife, and a three scarred lines carved deep from his left eye to his jaws. He reminded him of a stereotypical human depiction of a werewolf, without the human form of course. Classic huffs in frustration as the alternate Doggo snores loudly. Unable to find a way to escape, the skeleton leans against the wall, and hugs his knees. Since he’s stuck for now, might as well get some rest. A moment later, Classic drifts off to sleep.


	2. Chapter 2

Classic jolts awake as bucket of cold water splashes on him. He shivers as the droplets drip down his bones. The skeleton looks up in defiance while this Fell Doggo, Hound, as Classic nicknamed him, glances down on him in amusement. He slides a plate of cold water sausages in front of him.

“Eat,” Hound commands.

Finding no point in resisting from his position, Classic nibbles into the cold food, grimacing at the unsavory taste.

“Good boy,” the dog monster hums, clearly pleased, “Good pets get rewarded. You’ll need your strength.”

Not even halfway through the sausage, Classic asks, “What do you want from me?”

Hound snarls and kicks the plate into the wall, the glass shattering into pieces. The skeleton jumps and shields himself from the flying pieces, then huddles further up against the wall as if that would protect him.

“You don’t speak, unless I say you do, understand?!” the dog monster grabs Classic by the collar and bares his teeth.

The skeleton quickly nods and Hound drops him unceremoniously, returning to his previous mood, “Our king is cowardly. Monsterkind in this world, are going extinct and Asgore still refuses to use the Alternative Universe doorways to conquer other worlds. He’d rather sit upon his throne and let them to come to us.”

Hound spits.

“Not that it matters to you anymore, pet. Yer mine now. And yer gonna help me bring back our kind,” The monster unzips his dark green trousers and presents his long knotted cock in front of him.

Classic’s eye sockets widen and gulps at the size. Nearly a foot long, the pink flesh stands tall with a curved pointy tip and a bulbous thick knot at the base. Hound approaches, and Classic’s stomach churns. He quickly scrambles as far away as he can, forgetting the leash as he cries out for mercy. The fell monster grabs his skull and forces him on his knees, pinching his cheeks to open his mouth.

“If ya bite there will be consequences,” the alternate Doggo warns and slams his thick dog dick into Classic’s mouth.

Classic shrieks, this throat forming instantly. He squirms but Hound holds his head in place and rhythmically thrusts, reaching the back of his throat. The skeleton’s ecto tongue automatically forms, tasting the salty smoothness as it glides across the surface. The skeleton flails around, struggling to breathe, then a moment later, Hound pushes him away, throwing Classic on the ground.

He sighs in satisfaction, “That’s a fucking good mouth,”

Classic’s bones trembles, his head hanging low as he lets out a shuddered breath. The other monster ignores him.

“Can’t give ya my cum just yet, little pet. Gotta save it for my rut tomorrow,” Hound laughs and pats his balls, then frowns, his tone dropping an octave lower, “Tell me you liked it.”

“i-i liked it,” Classic echos, terrified of the consequences.

Hound smiles smugly, his ugly raggeded teeth did nothing to stop his foul breath, “Good pet. Here’s a treat,”

The Fell monster grabs something on the counter, and before Classic could see what it was, Hound shoves it into his mouth and forced his mouth closed. The skeleton has no choice but to swallow what feels like a small, salty tablet. His body tenses as he feels it go down his throat and seep into his soul, sizzling like water on a frying pan. Hound releases him and immediately Classic’s body lights on fire. His bones tingled and pricks with the lightest breeze and his mind turns hazy, vision blurring.

“I’ll be back tomorrow. Enjoy yerself tonight. You’ll need to prepare,” Hound laughs and exits the cabin, slamming the door shut behind him.

Classic writhes on the cold wooden floor, the collar chafing around his neck, but instead of pain, it sends sparks of pleasure down his spine. His body betrays him as a glowing blue ecto pussy forms, already slick with sticky juices, and his clit throbbing like a heartbeat. He cries softly, calling out for Red, for Papyrus, for anyone. But nobody came. Disgusted by this violation, Classic sits on his own hands, defying his body’s wishes and needs, despite his desperate desire. Instead, he tries to search for an escape, even with his head being too stuffed with cotton. First was to figure out a way to get the collar off him, or at least free him from the bed. He senses a buzz within the lock, laced together with magic. Classic grimaces. The only way to take off the collar is with Hound’s magic. But the chains however, are just normal steel. He looks around for any blunt object, but found none within his reach. He follows the links and his heart sinks as he finds them wrapped around the bed’s leg, but the metal burned and cooled so it blended together, impossible to free.

Desperate and delirious, Classic resorts to screaming, begging anyone to hear and save him. He screams and screams until the day breaks and his voice goes hoarse. As the birds sing their songs, the skeleton coughs, his body limp, numb, and exhausted, but the tingling arousal does not quell. Suddenly, the door swings open and Hound pounces in, eyes red as blood, saliva dripping from his snarling maw, his large erecting standing firm and tall as a statue. Classic gulps in fear.

His captor is in rut.

**Notes for the Chapter:**

> [ Chapter 3 will be posted on my tumblr b4 Ao3 ](http://www.casualbones.tumblr.com)


	3. Chapter 3

Hound pounces on Classic on the bed without a single word and claws at his clothes, tossing the shreds away in the corner. The skeleton screams and struggles to get away, but with the drug still in his system, his efforts remain fruitless. The Fell monster pins him down easily, his saliva dripping onto Classic’s cheek. Without wasting any time, Hound exposes his throbbing, rock hard cock, the knot the size of Asgore’s fist. Just seeing it sends the skeleton into his own heat, forced by the drugs, but the skeleton still resisted. Hound doesn’t care either way, and without much foreplay, he slams his cock in Classic’s pussy. The smaller monster cries out in pain, that slowly melts into pure, self-hating pleasure. With no means to escape, Classic gives up. He lays there, accepting the pounding thrusts. His ecto flesh expands deeply to fit the large insertion, the knot not even inside yet. Both pressure and ecstasy builds up in one concentrated spot, like butterflies in his stomach being stomped on. Hound growls and tightens his large claws around the skeleton’s throat, cutting off his airways. Classic’s eyes widen and rolls to the back of his head as his mind goes electrically numb. He grabs the other monster’s wrist and arches his back, squealing as he cums hard, his juices squirting all over the dog monster’s fur, but he keeps going. Finally, Hound’s dick expands and cum floods inside Classic’s ecto formed womb. The Fell monster pulls out and the skeleton’s legs flops on the mattress. Classic breathes harshly, silently crying into the pillow, just glad that it’s over with. He reminds himself that this isn’t him. He’s only feeling good because of the drugs, he doesn’t  _actually_ want this.

Hound chuckles, “Ya think I’m done, little pet? I’m done til I fill 3 litters in ya,”

Classic whines as Hound flips him over and thrusts inside his loose cunt again.

“Say you like my cock, slut,” Hound huffs.

“i like your cock,” Classic repeats dutifully.

“Call me your master,”

“i like your cock…master?”

Pleased, Hound jackhammers into Classic for hours, both of them cumming numerous times until the sheets become soaked with fluids and semen. The skeleton drools dumbly, the overwhelming continuous pleasure snuffing out every single thought. He speech slurs as he repeatedly moans, “cock” and “master”. Hound finally howls and slams his entire knot inside, releasing a typhoon of his seed in Classic’s expanding womb. The skeleton groans as Hound pets his head and throws his body back on the floor. Numb to everything, his eyes droops open and looks down, rubbing his big belly, almost like he’s pregnant, not filled to the brim with cum. The milky white swirls in his stomach, melding and compacting together. He breaks down into tears as the magic break down into five little souls, beating and glowing softly. Hound kneels down to Classic’s stomach, rubbing his large paw over the ecto-flesh, a proud grin stretching across his maw.

He pats the belly, “Good job, pet. You make a fine breeder. Here’s yer reward.”  

Hound forces Classic’s tongue out and places another pill, which he instinctively swallows. The same euphoria spreads through him, leaving him dazed and feeling really good. He rubs his belly, and giggles at how much it tickles. His magic tingles and forms around his torso, forming his well-endowed chest. Blue D cup breasts hang heavily, sagging slightly due to their weight. Dark, and thick indigo nipples perk up, his small areola surrounding it.

Hound tilts his head curiously and grabs a singular tit. He gently runs a thumb over the nipple, enlarging from the sudden contact. Classic sighs heaveningly, his spine shaking from the mini orgasm shuddering through him. Hound laughs slaps the skeleton’s chest, earning him another senusous moan.

“I’ll be back tomorrow. Be a good mommy and I’ll even bring you something you’ll like too,” the dog monster commands, leaving Classic alone once again in the cabin.

The five little souls beat in his womb, and the skeleton wraps his arm protectively around his little ones.


	4. Chapter 4

**Notes for the Chapter:**

> Chapter warnings: Exhibitionism, oral, pet play, lactation, nipple sucking

Classic’s mouth tightens, but he climbs on top of the sleeping dog monster and leans forward, his gigantic H cup tits swinging like a pendulum above Hound’s face. The dog monster stirs, and without opening his eyes, he grabs one of his breasts and laps at the thumb length nipple, encouraging the milky droplets to appear. Once the beads form, Hound takes a nipple in his mouth and suckles harshly. A spring of milk gushes from his breasts, his ever present pussy tingling with leaky pleasure. Classic whines and Hound bends his knee upward, allowing the skeleton to lewdly grind on it, his juices soaking the other monster’s thigh. His breath hitches as the dog monster gluttonously suckles his breakfast, gasping as the sparks ignite from the sensations. Careful with his nine month pregnant belly, the skeleton picks up his pace, rubbing his clit furiously against the furry leg.

“master! master!” Classic squeals, edging closer to ultimate bliss.

Hound chuckles darkly, and shoves his thumb into the other nipple. Sticky juices fly everywhere as Classic screams, cumming even more with the torrent of sweet milk erupting from both tits. Legs quivering and unable to support him, Classic collapses on his side. Hound rolls over and turns to the skeleton’s belly, gently rubbing it affectionately. Through the semi transparent ecto-flesh, five little skeletal pups slumber peacefully, though kicking occasionally. Classic whimpers as Hound spreads open his legs, exposing his slick cunt. Without hesitation, the dog monster dives in, his long tongue reaching all the way to the cervix. He massages through the walls, savoring every sweet and salty flavor exploding on his taste buds. Classic pants, tears prickling his eyes from the heightened sensitivity. As soon as Hound glides over his most sensitive spot, the skeleton’s hips buck, shoving himself closer to the dog’s face and lightly humps it for better reach. Hound pushes his Classic’s hips down with strong force, his growls of displeasure vibrating through his clit. A few seconds later, the skeleton cums with force, squirting all over the other monster’s face. Hound pulls away and licks himself cleanly, grinning at the skeleton before him, eyes rolled back with bliss and stomach large with his pups.

He sits up and slides off the bed, attaching a new leash to Classic’s collar. The skeleton tilts his head in confusion. After the five month mark, he was allowed to roam freely without his restraints, since with his pregnant belly, he couldn’t have gotten far and would’ve died in the woods before he could reach town anyway. He whimpers, wondering what he did wrong to anger his master.

“Relax, pet,” Hound pets his skull, “I think it’s about time I show you off,”

Classic perks up at the thought of going outside. Even with his small little freedom, he yearns to have the fresh air brush past against his face again, to see other people, and to not be confined to this tiny place. His cheeks nuzzles Hound’s large paw affectionately. After putting his shoes on, he taps his knee, and Classic obediently crawls on all fours to his side,  and happily accepts the little pill forced into his mouth. Already, he could feel his magic buzzing with glee. Hound opens the door and Classic pounces outside, rolling himself in the crispy snow, the cold air blasting his face. He pauses for a moment, allowing himself to bask in the fresh forest air, pine filling his nostrils. Hound tugs on his leash, and the skeleton snaps out of it, returning to his master. As the two of them trudge back into town, both Classic’s stomach and it tits drag across the snow, his nipples hard and leaking. With his increased sensitivity and the constant stimulation, the poor skeleton cums and squirts all over, leaving a trail of wet behind.

“Seriously? You came just from this?” Hound raises a brow, but says nothing more.

As they reach the edge of town, Classic stop, his breath hitching. His bones shake, eyes wide with clarity for the first time. He remembers Red’s hatred, his heated words, his biting attacks. How his anger twisted Classic’s soul. What would he do if he saw him now? Would he hurt him again? Would he look at him like he’s filth?

Hound impatiently tugs on the leash once more and Classic has no choice to follow. He trots through the quiet Snowdin town, onlookers gasping in surprise. Some hollers at the dog monster, others whistle, and some roll their eyes in jealousy.  Hound smirks proudly as he parades his pet to the other side of town, passing by two rough skeletons. Classic whimpers and keeps his head down, hoping that neither of them will recognize him.

“Classic? Classic!” Red gasps and kneels before him, his red glowing eyes flashing and his mouth slightly agape, “Holy shit, you’re alive.”

Classic whimpers and flinches, backing into Hound, terrified. He can’t trust Red, he can’t trust anyone but his master, and Red has hurt him in the past. The other skeleton tilts his head, then actually looks at Classic, specifically the collar around his neck, and his pregnant stomach, tits drooping to the ground and cunt glistening with juices. His eyes widen in horror and he backs away, like Classic was contagious with disease. Fists trembling, Red pounces on Hound, an array of bones pointing at the dog monster as the skeleton grabs his collar.

“WHAT DID YOU DO TO HIM?” Red snarls, his magic blazing fiercely.

Hound shoves him aside and throws a fist across his cheek, then kicks him in the stomach.

“Screw off, shithead. I saw him first,” Hound crosses his arms triumphantly.

“LIKE HELL I WILL!” Red gets back up on his feet and rolls up his sleeves, “HE DOESN’T BELONG WITH YOU!”

“Brother,” Edge grabs his hood and holds him back, “Don’t be an idiot. Or I will have to arrest you.”

“LET ME GO PAPYRUS! THAT’S  _CLASSIC!”_

**“** I know. But you go after him now, then he will charge you with destruction of property,” Edge, mouth twitches, but he remains calm.

“WHAT THE HELL ARE YOU TALKING ABOUT?!”

“The collaring laws, stupid,” Hound rolls his eyes and steps in front of Classic, “I collar him, I keep him. He’s mine now,”

“I’M GONNA CRUSH YOUR HEAD WITH MY FISTS,”

Classic’s eye lights darts between his master and his former lover. A sinking turmoil rages in his guts, like he’s going to throw up, his head dizzy and stuffy, unable to focus on anything. A part of him wants to run up to Red, and sob. To be in his comfort again is all that he wanted for the last nine months, especially now, knowing that he still cares about him. But his master, how can he leave his master? He thinks about the sweet suckles he blesses him every morning, the hard thick cock penetrating his very core. His cum filling his womb forever and ever and ever… A sharp pain punches his pelvis, causing him to yelp and collapse on his side. He gasps, clutching his belly as a burst of water explodes inside him, the fluid dripping down his legs. Hound glances over nonchalantly while Red calls out his name in fear. The pain shoots through his spine and tears spill out of his eye sockets. Classic reaches out to Hound, who gently picks up him and smirks at the Fell skeletons before him.

“I would love to continue this, but it looks like it’s about time I become a daddy,” and with that, Classic and Hound disappears once again behind the woods.  


	5. Chapter 5

**Notes for the Chapter:**

> Chapter warnings: Birthing, Squirting, Labor, Mind break

Hound takes his sweet time returning to the cabin, leaving Classic to writhe in agony. He tosses the skeleton on the bed and hold him from behind, using his large body to support them. The dog monster rubs the ecto stomach, watching the pups actively kick and swarm through the exit all at once, through the translucent ecto stomach. Classic wails, clutching his belly as sweat drips down his skull, every contraction feeling like a thousand punches in the stomach. He wails loudly, pushing as hard as he can, the milk streaming down from his hard dark nipples.

Hound’s fingers snakes over the skeleton’s large clitoris, rubbing it between his forefinger and his index as another squirt of water erupts from his pussy. His painful wails turns into pleasured moans. He grinds on the hand, begging for more and more stimulation. Hound happily complies, stroking it more fiercely as another contraction hits the skeleton, just an oragasm rips through his body. He screams as the first pup slides out easily, an explosion of fireworks bursting in his eyes. Hound continues to play with Classic’s clit, as the second pup slides out of the skeleton’s womb. He huffs pleasurably, feeling every excruciating movement of the child and he once again, cums hard, squirting all over the bed. His tongue lolls out, dripping with saliva. Every time a pup is released, a continuous, mind breaking ecstasy shatters him, until he’s laying in bed, cumming one last time from how light he feels.

Hound tends to the pups while Classic passes out. He coos affectionately and cleans them gently with a warm towel, and place them all in a doggy bed by the fire. He hasn’t named them yet, but he knows that they’ll be great. Each of them yawns and drift off into slumber. Suddenly, the door kicks down, startling Classic awake with fear and he scampers behind Hound, cowering on this knees. Red, Edge, and Undyne enter the cabin, with the two royal guards looking bored and Red raging in fury.

“let classic go,” the Underfell skeleton growls.

Hound just rolls his eyes, “I already told you. I collared him. Which means he’s mine,”

“That’s actually why we’re here,” Undyne stretches, but couldn’t look any more disinterested in settling such petty disputes, “Red says he claimed ownership of Classic before he could get the collar. There is evidence of ownership relations through Alphys’s camera.”

Hound snarls.

“However, as I can see… Classic already gave birth. So technically, he’s also Hound’s property.” Undyne says as she glances at the pups.

“what?!” Red yells.

The Captain only yawns, “Welp. I guess you’re just gonna have to ask Classic who he wants to go with.”

Red looks over at his alternate, his eyelights soft and loving, urging him to come to him. Classic’s eyes shift from Hound to Red.

“You may speak,” Hound orders.

“i… i… “ Classic takes a deep breath and claws at the dog monster’s pants, “i want to stay with master! i want his thick knot fucking me stupid again! i want master’s cum inside me! please fuck me again master, i want to be pregnant again!”

“classic…” Red recoils, his expression falling in betrayal.

Classic giggles as he starts groping and licking Hound’s boner through his pants, present company be damned. Hound laughs as both Edge and Undyne drag Red outside and disappear back into town. Classic starts unzipping his master’s pants, and wraps his enormous tits around his thick cock, milking him for his delicious cum.

Hound rams his length into Classic’s, who then takes it deep in his throat and looks up in pure adoration for his master.

“Good pet.”

**Author's Note:**

> [ Follow me on tumblr for earlier updates ](http://casualbones.tumblr.com)


End file.
